package com.atguigu.springcloud.controller.lb;

import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * Created with IntelliJ IDEA.
 *
 * @Auther: hjj
 * @Date: 2021/11/09/11:49
 * @Description: 自己实现负载均衡
 */
@Component
public class MyLB implements LoadBalancer {

    private AtomicInteger atomicInteger = new AtomicInteger(0);

    public final int getAndInterment(){
        int current;
        int next;
        do {
            current = this.atomicInteger.get();
            next = current>=2147483647 ? 0 : current+1;
        }while (!atomicInteger.compareAndSet(current,next));
        System.out.println("***第几次访问，次数next:"+next);
        return next;
    }

    @Override
    public ServiceInstance instances(List<ServiceInstance> serviceInstances) {
        int index = getAndInterment()%serviceInstances.size();
        return serviceInstances.get(index);
    }
}
